Which class is happiest, the rich, the middle class or the poor? A very successful executive of a large organization touches upon this vital subject in a long letter to all his salesmen. He uses as his text a passage from Robinson Crusoe which included this: ""My Father bid me observe it, and I should always find that the calamities of life were shared among the upper and lower part of mankind; but that the middle station had the fewest disasters, and were not exposed to so many vicissitudes as the higher or lower part of mankind.